The new combining character "HORIZONTAL FLIP COMBINING CHARACTER" combines with any emoji and flips it left-to-right.
Many emoji have a standard directionality, but depending on context this may or may not be the direction that best conveys the author's intent.
Consider the common formula:
"JFK✈️SFO" for the statement "Flying from JFK to SFO"
Because the airplane emoji faces rightward, it naturally conveys the author's intended meaning.
But pity the traveller who makes that trip by any other means of transportation. 🚌, 🚄, 🚁, ⛴ are all leftward-facing characters. This forces the author into a choice between:
- JFK🚄SFO, which seems to imply the oppsite trip from what is intended, or:
- SFO🚄JFK, where the emoji's direction correctly implies the direction of travel but by torturing the grammar of the sentence.
With HORIZONTAL FLIP COMBINING CHARACTER, it would be possible to form the correct sentence:
JFK (horizontally-flipped train) SFO
Many other sentences, difficult or awkward to express with existing directions of emoji, would become natural if their directions could be flipped.
Many emoji input methods already implement a two-layered selection method, to allow authors to first pick a base glyph and then select a skin tone. Common user interfaces for this include a double-click or long tap to expose the secondary selection choices. I propose that for glyphs that do not depict human beings, where skin tone options are not applicable, the secondary selection should allow choosing between the default and flipped direction of the glyph.